简述了基于ROACH和Xilinx System Generator平台的接收机数字后端系统的设计与实现。介绍了Zoom-PFB算法原理,讨论了该算法的核心部分低通滤波和抽取的现场可编程门阵列(Field-Programmable Gate Array,FPGA)实现。针对谱线观测局部高...简述了基于ROACH和Xilinx System Generator平台的接收机数字后端系统的设计与实现。介绍了Zoom-PFB算法原理,讨论了该算法的核心部分低通滤波和抽取的现场可编程门阵列(Field-Programmable Gate Array,FPGA)实现。针对谱线观测局部高精度分辨率的需要,给出了将400 MHz带宽分为带宽25 MHz的16个通道,对其中任一通道做通道数为6 k、频率分辨率为4 k Hz的频谱细化系统的具体设计方案。在实验室条件下,对该数字后端的性能进行了分析和测试,并以4.5 m口径X/Y结构天线进行银道面中性氢谱线观测检验其应用效果,验证了方案的可行性。展开更多
To protect the wellbeing of research animals,certain non-invasive measures are in increasing need to facilitate an early diagnosis of health and toxicity.In this study,feces specimen was collected from adult zebrafish...To protect the wellbeing of research animals,certain non-invasive measures are in increasing need to facilitate an early diagnosis of health and toxicity.In this study,feces specimen was collected from adult zebrafish to profile the metabolome fingerprint.Variability in fecal metabolite composition was also distinguished as a result of aging,perfluorobutanesulfonate(PFBS)toxicant,and fecal transplantation.The results showed that zebrafish feces was very rich in a diversity of metabolites that belonged to several major classes,including lipid,amino acid,carbohydrate,vitamin,steroid hormone,and neurotransmitter.Fecal metabolites had functional implications to multiple physiological activities,which were characterized by the enrichment of digestion,absorption,endocrine,and neurotransmission processes.The high richness and functional involvement of fecal metabolites pinpointed feces as an abundant source of diagnostic markers.By comparison between young and aged zebrafish,fundamental modifications of fecal metabolomes were caused by aging progression,centering on the neuroactive ligand-receptor interaction pathway.Exposure of aged zebrafish to PFBS pollutant also significantly disrupted the metabolomic structure in feces.Of special concern were the changes in fecal hormone intermediates after PFBS exposure,which was concordant with the in vivo endocrine disrupting effects of PFBS.Furthermore,itwas intriguing that transplantation of young zebrafish feces efficientlymitigated the metabolic perturbation of PFBS in aged recipients,highlighting the health benefits of therapeutic strategies based on gut microbiota manipulation.In summary,the present study provides preliminary clues to evidence the non-invasive advantage of fecal metabolomics in the early diagnosis and prediction of physiology and toxicology.展开更多
Per-and polyfluorinated alkyl substances(PFASs) are commonly used in industrial processes and daily life products.Because they are persistent, they accumulate in the environment, wildlife and humans.Although many stud...Per-and polyfluorinated alkyl substances(PFASs) are commonly used in industrial processes and daily life products.Because they are persistent, they accumulate in the environment, wildlife and humans.Although many studies have focused on two of the most representative PFASs, PFOS and PFOA, the potential toxicity of short-chain PFASs has not yet been given sufficient attention.We used a battery of assays to evaluate the toxicity of several four-carbon and six-carbon perfluorinated sulfonates and carboxyl acids(PFBS,PFHxS, PFBA and PFHxA), with a human mesenchymal stem cell(hMSC) system.Our results demonstrate significant cyto-and potential developmental toxicity for all the compounds analyzed, with shared but also distinct mechanisms of toxicity.Moreover, the effects of PFBS and PFHxS were stronger than those of PFBA and PFHxA, but occurred at higher doses compared to PFOS or PFOA.展开更多
基金supported by the National Natural Science Foundation of China(No.22006159)the Natural Science Foundation of Hubei Province,China(No.2021CFA086)the Innovative Team Program of Natural Science Foundation of Hubei Province,China(No.2021CFA032).
文摘To protect the wellbeing of research animals,certain non-invasive measures are in increasing need to facilitate an early diagnosis of health and toxicity.In this study,feces specimen was collected from adult zebrafish to profile the metabolome fingerprint.Variability in fecal metabolite composition was also distinguished as a result of aging,perfluorobutanesulfonate(PFBS)toxicant,and fecal transplantation.The results showed that zebrafish feces was very rich in a diversity of metabolites that belonged to several major classes,including lipid,amino acid,carbohydrate,vitamin,steroid hormone,and neurotransmitter.Fecal metabolites had functional implications to multiple physiological activities,which were characterized by the enrichment of digestion,absorption,endocrine,and neurotransmission processes.The high richness and functional involvement of fecal metabolites pinpointed feces as an abundant source of diagnostic markers.By comparison between young and aged zebrafish,fundamental modifications of fecal metabolomes were caused by aging progression,centering on the neuroactive ligand-receptor interaction pathway.Exposure of aged zebrafish to PFBS pollutant also significantly disrupted the metabolomic structure in feces.Of special concern were the changes in fecal hormone intermediates after PFBS exposure,which was concordant with the in vivo endocrine disrupting effects of PFBS.Furthermore,itwas intriguing that transplantation of young zebrafish feces efficientlymitigated the metabolic perturbation of PFBS in aged recipients,highlighting the health benefits of therapeutic strategies based on gut microbiota manipulation.In summary,the present study provides preliminary clues to evidence the non-invasive advantage of fecal metabolomics in the early diagnosis and prediction of physiology and toxicology.
基金supported by the National Natural Science Foundation of China (Nos.21876197, 21577166, 21707160)the Chinese Academy of Sciences (Nos.XDB14040301, 29[2015]30, QYZDJ-SSW-DQC017)the K.C.Wong Education Foundation.
文摘Per-and polyfluorinated alkyl substances(PFASs) are commonly used in industrial processes and daily life products.Because they are persistent, they accumulate in the environment, wildlife and humans.Although many studies have focused on two of the most representative PFASs, PFOS and PFOA, the potential toxicity of short-chain PFASs has not yet been given sufficient attention.We used a battery of assays to evaluate the toxicity of several four-carbon and six-carbon perfluorinated sulfonates and carboxyl acids(PFBS,PFHxS, PFBA and PFHxA), with a human mesenchymal stem cell(hMSC) system.Our results demonstrate significant cyto-and potential developmental toxicity for all the compounds analyzed, with shared but also distinct mechanisms of toxicity.Moreover, the effects of PFBS and PFHxS were stronger than those of PFBA and PFHxA, but occurred at higher doses compared to PFOS or PFOA.